1. Field of the Invention
The present invention relates to a solid polymer electrolyte fuel cell (hereinafter simply termed a “fuel cell”), and to a frame which is used therein; and, more particularly, to a fuel cell which incorporates a separator which contacts against an MEA (membrane electrode assembly) which is included in the fuel cell, and to a frame which is used therein.
2. Description of the Related Art
A fuel cell includes an MEA which has electrodes on the surfaces of an electrolyte layer which is made from an ion exchange layer. Such an MEA includes, on its one surface, a fuel electrode (an anode), which is an electrode which reacts with a fuel gas (hydrogen), and, on its other surface, an oxidant electrode (a cathode) which reacts with an oxidant gas (oxygen); and a predetermined chemical reaction takes place upon such an MEA, thus enabling electricity to be extracted.
There is a per se known structure for this kind of fuel cell, as for example disclosed in Japanese Laid-Open Patent Publication 2003-77499, comprising an MEA, resin frames which are disposed on the front and the rear surfaces of the MEA and which sandwich a peripheral edge portion of the MEA and thereby fix it, and separators which are disposed on the front and the rear surfaces of the MEA of which the peripheral edge portion is sandwiched and fixed by the resin frames, and on which collector portions are formed which contact against the MEA.
In the fuel cell having the structure described above, the resin frames sandwich and fix the peripheral edge portion of the MEA. In order for the predetermined chemical reaction to progress in a smooth manner upon the MEA and for electricity to be extracted, it is desirable for the MEA to be held flat, and, for this, with the fuel cell of the above described structure, it is necessary to strive for preventing the occurrence of wrinkling of the MEA, the peripheral edge portion of which is sandwiched and fixed by the resin frames.
With the fuel cell of the above described structure, since the MEA is fixed by its peripheral edge portion being sandwiched by the resin frames, accordingly it is not possible to provide any collector portion at the peripheral edge portion of the MEA. Due to this, there has been the problem that it is not possible to collect any electricity from the peripheral edge portion of the MEA, even though fuel gas and oxidant gas are supplied to this peripheral edge portion of the MEA.
The objective of the present invention is to provide a fuel cell in which the peripheral edge portion of an MEA can be utilized for generating electricity, and a frame which is used therein.